Question

Which of these combinations is most likely to be present before ovulation occurs ?

• A. FSH, corpus luteum, estrogen, secretory uterine lining
• B. LH, corpus luteum, progesterone, secretory uterine lining
• C. FSH, follicle, estrogen, uterine lining becoming thick
• D. Luteinising hormone (LH), follicle, progesterone, thick uterine lining

Answer 1

Answer: (C)

FSH, follicle, estrogen, uterine lining becoming thick

In females there is a cyclical pattern of hormone secretion by the ovaries. This pattern of hormone secretion results in the ovulation of a single egg each cycle, and coordinates changes in the uterus so that it is ready to house a developing embryo should that egg become fertilized. The structure in the ovary that contains the oocyte and support cells is called a follicle. Those that are not developing are called primordial follicles, and consist of an oocyte in meiotic arrest surrounded by a single layer of follicle cells. The first part of the hormonally-regulated cycle is called the growth phase. During the growth phase, a cohort of follicles that have undergone initial development are stimulated to develop further by rising concentrations of gonadotropins, follicle stimulating hormone (FSH) and luteinizing hormone (LH). The granulosa cells greatly increase in size, the basement membrane breaks down, and the structure is invaded by blood vessels. The corpus luteum is an important endocrine structure, secreting progesterone and estrogen that is necessary to prepare the uterus for implantation and early pregnancy. Estrogen causes the lining to grow and thicken to prepare the uterus for pregnancy.

So the correct option is 'FSH, follicle, estrogen, uterine lining becoming thick'.